Hi Katie,
Regarding the gearbox leak, I think it's not technically a leak because it's supposed to be dry on both sides of the joint (inside and outside). The leak is coming into the clutch cavity from either a shaft seal on the transmission or from the rear seal of the crankshaft, depending on whether it is engine oil or transmission fluid, as I understand the system. Since the bell housing-to-transmission joint is supposed to be dry, there is no need to have a gasket in the joint.
Removing the transmission will reveal the "real" source of the leak.
Mine leaks too, and I fabricated an aluminum strap-on cup that holds a "maxipad" to keep my garage floor dry, and I change it about once a month. No laughing permitted!
I am tired of changing it, so I am preparing to remove the transmission and rebuild anything that is broken. It is probably a much bigger job than 4 hours. I have not done it before.
Good luck.
Tom Kizer